What do Bill Clinton, Mark Zuckerberg, Bing Crosby, Fred Rogers, Howie Mandel and Mark Twain have in common? All of these men suffered or are suffering with color blindness.

Color blindness is a genetic condition that disables the light-sensitive cells in a person’s retina from accurately responding to the inconsistencies in light wavelengths, which permit us to distinguish the differences of a spectrum of colors.

Contrary to popular belief, it is extremely rare for a color blind person to see only in shades of gray. The term “color blindness” does not refer to an individual’s literal blindness of every color, but his or her inability to distinguish a significant difference between two colors. According to Colblindor, 99 percent of all color blind people are not actually color blind, but color deficient.

The most frequently inherited type of color blindness (the inability to distinguish red from green) originates from a typical X-linked recessive gene. Although more women are carriers of the color blindness gene than men, color blindness affects males significantly more than females. According to Prevent Blindness America, an estimated 8 percent of all men suffer from color blindness, while only 0.5 percent of all women have color vision problems.

Color blindness can also occur from aging, eye injury, side effects of certain medications, and other eye problems, such as glaucoma, macular degeneration, cataracts or diabetic retinopathy.

Ever wondered if you have issues with color vision? If so, go to http://bit.ly/1g5kQCs to take a quick online color vision test.